Plating apparatus, plating method and recording medium

ABSTRACT

A plating apparatus can suppress a time period during which a plating liquid is used in a plating from being reduced. In the plating apparatus 1, after a plating liquid supply unit 53 supplies, to a substrate W1, a plating liquid which exerts a preset plating performance within a preset concentration range and which has an initial temperature adjusted to be lower than a preset plating temperature; and an initial concentration adjusted such that a concentration of the plating liquid at a moment when a temperature of the plating liquid has reached the preset plating temperature is equal to or higher than a lower limit of the preset concentration range and equal to or below a median value of the preset concentration range, a plating liquid heating unit 63 heats the plating liquid supplied to the substrate W1 to the preset plating temperature.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Japanese Patent Application No.2015-212218 filed on Oct. 28, 2015, the entire disclosures of which areincorporated herein by reference.

TECHNICAL FIELD

The embodiments described herein pertain generally to a platingapparatus and a plating method. Further, the embodiments also relate toa recording medium having stored thereon a program for performing theplating method.

BACKGROUND

A plating liquid exerts a preset plating performance within a presetconcentration range. When initially preparing the plating liquid in aplating bath, the plating liquid is adjusted to have the presetconcentration range where the preset plating performance is achievedfrom the beginning. Then, during a plating, the concentration of theplating liquid is regulated to the preset concentration range where thepreset plating performance is achieved. Patent Document 1 discloses aconcentration management method and a concentration management systemfor a plating liquid.

Patent Document 2 describes a batch type plating apparatus. In the batchtype plating apparatus, a plating liquid adjusted to have a presetconcentration range where a preset plating performance can be achievedis initially prepared in a plating bath, and the plating upon a multiplenumber of substrates are performed in the plating bath at the same time.If the concentration of the plating liquid is decreased as a platingcomponent in the plating liquid is consumed through the plating, theplating component is supplemented, and the plating is repeatedlyperformed within the plating bath. In the batch type plating apparatus,moisture is evaporated from the plating liquid in the plating bath.Since, however, the amount of the plating liquid in the plating bath islarge, the decrease of the concentration of the plating liquid caused bythe consumption of the plating component is more dominant than anincrease of the concentration of the plating liquid caused by theevaporation of the moisture. Thus, the concentration of plating liquidin the plating bath tends to be decreased.

Patent Document 3 describes a single-substrate type plating apparatus.In the single-substrate type plating apparatus, a plating liquid whichis adjusted to have a preset concentration range where a preset platingperformance is achieved is supplied to a single sheet of substrate, anda plating of the single sheet of substrate is performed. The amount ofthe plating liquid supplied to the single sheet of substrate is muchsmaller than the amount of the plating liquid in the plating bath in thebatch type plating apparatus. Thus, the increase of the concentration ofthe plating liquid caused by the evaporation of the moisture is moredominant than the decrease of the concentration of the plating liquidcaused by the consumption of the plating component, so that theconcentration of the plating liquid supplied to the single sheet ofsubstrate tends to be increased.

Patent Document 1: Japanese Patent Laid-open Publication No. 2003-253453

Patent Document 2: Japanese Patent Laid-open Publication No. 2013-104118

Patent Document 3: Japanese Patent Laid-open Publication No. 2013-112845

In the single-substrate type processing apparatus, after a platingliquid having an initial temperature adjusted to be below a presetplating temperature and an initial concentration adjusted to be in apreset concentration range where a preset plating performance isachieved is supplied to a single sheet of substrate, the suppliedplating liquid is heated to the preset plating temperature, and aplating is performed with the plating liquid which is heated to thepreset plating temperature. In this case, during a time period before atemperature of the plating liquid reaches the preset platingtemperature, a plating component in the plating liquid is hardlyconsumed, whereas moisture in the plating liquid is evaporated. As aresult, the concentration of the plating liquid is increased. After thetemperature of the plating liquid reaches the preset platingtemperature, the plating component in the plating liquid is consumed.Since, however, the heating of the plating liquid is continued, theconcentration of the plating liquid is increased. That is to say, sincethe increase of the concentration of the plating liquid caused by theevaporation of the moisture in the plating liquid is more dominant thanthe decrease of the concentration of the plating liquid caused by theconsumption of the plating component in the plating liquid, theconcentration of the plating liquid increases even after the temperatureof the plating liquid reaches the preset plating temperature. Theplating liquid can be used until its concentration reaches an upperlimit of the preset concentration range. Since, however, theconcentration of the plating liquid is already increased at a time whenthe temperature of the plating liquid has reached the preset platingtemperature, a time period before the concentration of the platingliquid reaches the upper limit of the preset concentration range, thatis, a time period during which the plating liquid can be used in theplating is shortened.

SUMMARY

In view of the foregoing, exemplary embodiments provide a platingapparatus and a plating method capable of suppressing a time periodduring which a plating liquid can be used in a plating from beingreduced. Further, the exemplary embodiments also provide a recordingmedium having stored thereon a program for implementing this platingmethod.

The present disclosure includes following exemplary embodiments.

(1) A plating apparatus having a plating device configured to perform aplating on a substrate at a preset plating temperature; and a controllerconfigured to control an operation of the plating device,

wherein the plating device comprises:

a plating liquid supply unit configured to supply, to the substrate, aplating liquid which allowed to exert a preset plating performancewithin a preset concentration range; and

-   -   a plating liquid heating unit configured to heat the plating        liquid supplied to the substrate to the preset plating        temperature,    -   wherein the plating liquid supplied to the substrate from the        plating liquid supply unit has an initial temperature adjusted        to be lower than the preset plating temperature, and an initial        concentration adjusted such that a concentration of the plating        liquid at a moment when a temperature of the plating liquid has        reached the preset plating temperature while being heated by the        plating liquid heating unit is equal to or higher than a lower        limit of the preset concentration range and equal to or below a        median value of the preset concentration range, and

the controller controls the plating liquid supply unit and the platingliquid heating unit to perform, by supplying a preset amount of theplating liquid to the substrate a single time and heating the suppliedplating liquid to the preset plating temperature, the plating with theplating liquid heated to the preset plating temperature.

(2) The plating apparatus as described in (1),

wherein the initial concentration is adjusted such that theconcentration of the plating liquid at the moment when the temperatureof the plating liquid has reached the preset plating temperature isclose to the lower limit of the preset concentration range.

(3) The plating apparatus as described in (1) or (2),

wherein the initial concentration is adjusted to be lower than the lowerlimit of the preset concentration range.

(4) The plating apparatus as described in any one of (1) to (3),

wherein the plating device is equipped with a top plate disposed abovethe substrate, and

when the plating liquid supplied to the substrate is heated by theplating liquid heating unit, a space in which vapor generated from theplating liquid supplied to the substrate stays is formed between thesubstrate and the top plate.

(5) A plating method of performing a plating on a substrate at a presetplating temperature, the plating method comprising:

a plating liquid supplying process of supplying, to the substrate, aplating liquid which exerts a preset plating performance within a presetconcentration range and which has an initial temperature adjusted to belower than the preset plating temperature; and an initial concentrationadjusted such that a concentration of the plating liquid at a momentwhen a temperature of the plating liquid has reached the preset platingtemperature is equal to or higher than a lower limit of the presetconcentration range and equal to or below a median value of the presetconcentration range; and

a plating liquid heating process of heating the plating liquid suppliedto the substrate to the preset plating temperature,

wherein a preset amount of the plating liquid is supplied to thesubstrate a single time in the plating liquid supplying process, and

in the plating liquid heating process, the plating liquid supplied inthe plating liquid supplying process is heated to the preset platingtemperature, and the plating is performed with the plating liquid heatedto the preset plating temperature.

(6) The plating method as described in (5),

wherein the initial concentration is adjusted such that theconcentration of the plating liquid at the moment when the temperatureof the plating liquid has reached the preset plating temperature isclose to the lower limit of the preset concentration range.

(7) The plating method as described in (5) or (6),

wherein the initial concentration is adjusted to be lower than the lowerlimit of the preset concentration range.

(8) The plating method as described in any one of (5) to (7),

wherein the plating liquid heating process is performed in a state wherea space in which vapor generated from the plating liquid supplied to thesubstrate stays is formed between the substrate and a top plate disposedabove the substrate.

(9) A computer-readable recording medium having stored thereoncomputer-executable instructions that, in response to execution, cause aplating apparatus to perform a plating method as described in any one of(5) to (8).

According to the exemplary embodiments as stated above, it is possibleto provide a plating apparatus and a plating method capable ofsuppressing the time period during which the plating with the platingliquid is performed from being reduced. The exemplary embodiments alsoprovide a recording medium having stored thereon a computer-executableprogram for implementing this plating method.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

In the detailed description that follows, embodiments are described asillustrations only since various changes and modifications will becomeapparent to those skilled in the art from the following detaileddescription. The use of the same reference numbers in different figuresindicates similar or identical items.

FIG. 1 is a schematic diagram illustrating a configuration of a platingapparatus according to an exemplary embodiment;

FIG. 2 is a schematic plan view illustrating a configuration of aplating unit included in the plating apparatus shown in FIG. 1; and

FIG. 3 is a schematic cross sectional view illustrating a configurationof a plating device included in the plating unit shown in FIG. 2.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part of the description. In thedrawings, similar symbols typically identify similar components, unlesscontext dictates otherwise. Furthermore, unless otherwise noted, thedescription of each successive drawing may reference features from oneor more of the previous drawings to provide clearer context and a moresubstantive explanation of the current exemplary embodiment. Still, theexemplary embodiments described in the detailed description, drawings,and claims are not meant to be limiting. Other embodiments may beutilized, and other changes may be made, without departing from thespirit or scope of the subject matter presented herein. It will bereadily understood that the aspects of the present disclosure, asgenerally described herein and illustrated in the drawings, may bearranged, substituted, combined, separated, and designed in a widevariety of different configurations, all of which are explicitlycontemplated herein.

<Configuration of Plating Apparatus>

Referring to FIG. 1, a configuration of a plating apparatus according toan exemplary embodiment will be explained. FIG. 1 is a schematic diagramillustrating the configuration of the plating apparatus according to theexemplary embodiment.

As depicted in FIG. 1, the plating apparatus 1 according to theexemplary embodiment includes a plating unit 2 and a controller 3configured to control an operation of the plating unit 2.

The plating unit 2 is configured to perform various processings on asubstrate. The various processings performed by the plating unit 2 willbe described later.

The controller 3 is implemented by, for example, a computer, andincludes an operation controller and a storage unit. The operationcontroller is implemented by, for example, a CPU (Central ProcessingUnit) and is configured to control the operation of the plating unit 2by reading and executing a program stored in the storage unit. Thestorage unit is implemented by a storage device such as, but not limitedto, a RAM (Random Access Memory), a ROM (Read Only Memory) or a harddisk, and stores thereon a program for controlling various processingsperformed in the plating unit 2. Further, the program may be recorded ina computer-readable recording medium, or may be installed from therecording medium to the storage unit. The computer-readable recordingmedium may be, for example, a hard disc (HD), a flexible disc (FD), acompact disc (CD), a magnet optical disc (MO), or a memory card. Therecording medium has stored thereon a program that, when executed by acomputer for controlling an operation of the plating apparatus 1, causesthe plating apparatus 1 to perform a plating method to be describedlater under the control of the computer.

<Configuration of Plating Unit>

Referring to FIG. 2, a configuration of the plating unit 2 will bediscussed. FIG. 2 is a schematic plan view illustrating theconfiguration of the plating unit 2. In FIG. 2, dashed lines indicatesubstrates.

The plating unit 2 includes a carry-in/out station 21; and a processingstation 22 provided adjacent to the carry-in/out station 21.

The carry-in/out station 21 includes a placing section 211; and atransfer section 212 provided adjacent to the placing section 211.

In the placing section 211, a plurality of transfer containers(hereinafter, referred to as “carriers C”) is placed to accommodate aplurality of substrates horizontally.

The transfer section 212 is provided with a transfer device 213 and adelivery unit 214. The transfer device 213 is provided with a holdingmechanism configured to hold a substrate. The transfer device 213 isconfigured to be movable horizontally and vertically and pivotablearound a vertical axis.

The processing station 22 includes plating devices 5. In the presentexemplary embodiment, the number of the plating devices 5 provided inthe processing station 22 may be two or more, but it is also possible toprovide only one plating device 5. The plating devices 5 are arranged atboth side of a transfer path 221 which is extended in a presetdirection.

The transfer path 221 is provided with a transfer device 222. Thetransfer device 222 includes a holding mechanism configured to hold asubstrate, and is configured to be movable horizontally and verticallyand pivotable around a vertical axis.

In the following description, a substrate before being loaded into theplating device 5 will be referred to as “substrate W0”; a substratewhich has been loaded into the plating device 5 and is yet to beunloaded from the plating device 5 will be referred to as “substrateW1”; and a substrate after being unloaded from the plating device 5 willbe referred to as “W2.”

In the plating unit 2, the transfer device 213 of the carry-in/outstation 21 is configured to transfer the substrates W0 and W2 betweenthe carriers C and the delivery unit 214. To elaborate, the transferdevice 213 takes out the substrate W0 from the carrier C placed in theplacing section 211, and then, places the substrate W0 in the deliveryunit 214. Further, the transfer device 213 takes out the substrate W2which is placed in the delivery unit 214 by the transfer device 222 ofthe processing station 22, and then, accommodates the substrate W2 inthe carrier C of the placing section 211.

In the plating unit 2, the transfer device 222 of the processing station22 is configured to transfer the substrates W0 and W2 between thedelivery unit 214 and the plating device 5 and between the platingdevice 5 and the delivery unit 214. To elaborate, the transfer device222 takes out the substrate W0 placed in the delivery unit 214 andcarries the substrate W0 into the plating device 5. Further, thetransfer device 222 takes out the substrate W2 from the plating device 5and places the substrate W2 in the delivery unit 214.

<Configuration of Plating Device>

Referring to FIG. 3, a configuration of the plating device 5 will beexplained. FIG. 3 is a schematic cross sectional view illustrating theconfiguration of the plating device 5.

The plating device 5 is configured to perform a plating on a substrateW1 at a preset plating temperature. The plating performed by the platingdevice 5 is an electroless plating. Here, a substrate processingperformed by the plating device 5 is not particularly limited as long asit includes the plating. That is, the substrate processing performed bythe plating device 5 may include other processings than the plating. Inthe present exemplary embodiment, the substrate processing performed bythe plating device 5 includes the plating and a pre-processing which isperformed prior to the plating.

The plating device 5 includes a chamber 51, and is configured to performa substrate processing including the plating within the chamber 51.

The plating device 5 is provided with a substrate holding unit 52configured to hold the substrate W1. The substrate holding unit 52includes a rotation shaft 521 extended in a vertical direction withinthe chamber 51; a turntable 522 provided at an upper end portion of therotation shaft 521; a chuck 523 provided on an outer peripheral portionof a top surface of the turntable 522 and configured to support an edgeportion of the substrate W1; and a driving unit 524 configured to rotatethe rotation shaft 521.

The substrate W1 is supported by the chuck 523 to be horizontally heldon the turntable 522 while being slightly spaced apart from the topsurface of the turntable 522. In the present exemplary embodiment, amechanism of holding the substrate W1 by the substrate holding unit 52is of a so-called mechanical chuck type in which the edge portion of thesubstrate W1 is held by the chuck 523 which is configured to be movable.However, a so-called vacuum chuck type of vacuum attracting a rearsurface of the substrate W1 may be used instead.

A base end portion of the rotation shaft 521 is rotatably supported bythe driving unit 524, and a leading end portion of the rotation shaft521 sustains the turntable 522 horizontally. If the rotation shaft 521is rotated, the turntable 522 placed on the upper end portion of therotation shaft 521 is rotated, and, as a result, the substrate W1 whichis held on the turntable 522 by the chuck 523 is also rotated. Thecontroller 3 controls the driving unit 524 to adjust, e.g., a rotationtiming, a rotational speed and a rotation time of the substrate W1.

The plating device 5 includes a plating liquid supply unit 53 configuredto supply a plating liquid M1 onto the substrate W1 which is held by thesubstrate holding unit 52. The plating liquid supply unit 53 is equippedwith a nozzle 531 configured to discharge the plating liquid M1 towardthe substrate W1 held by the substrate holding unit 52; and a platingliquid supply source 532 configured to supply the plating liquid M1 tothe nozzle 531. The plating liquid M1 is stored in a tank of the platingliquid supply source 532, and the plating liquid M1 is supplied into thenozzle 531 from the plating liquid supply source 532 through a supplypassageway 534 which is equipped with a flow rate controller such as avalve 533. The controller 3 controls, for example, a supply timing and asupply amount of the plating liquid M1 by controlling the plating liquidsupply unit 53.

The plating liquid M1 is an autocatalytic (reduction) plating liquid forelectroless plating. The plating liquid M1 contains a metal ion such asa cobalt (Co) ion, a nickel (Ni) ion, a tungsten (W) ion, a copper (Cu)ion, a palladium (Pd) ion or a gold (Au) ion; and a reducing agent suchas hypophosphorous acid or dimethylamineborane. Further, in theautocatalytic (reduction) electroless plating, the metal ion in theplating liquid M1 is reduced by the electrons emitted in an oxidationreaction of the reducing agent in the plating liquid M1 and isprecipitated as a metal, so that a metal film (plating film) is formed.The plating liquid M1 may further contain an additive or the like. Themetal film (plating film) formed by the plating with the plating liquidM1 may be, by way of non-limiting example, CoWB, CoB, CoWP, CoWBP, NiWB,NiB, NiWP, NiWBP, or the like. P in the metal film (plating film) isoriginated from the reducing agent (e.g., hypophosphorous acid)containing P, and B in the plating film is originated from the reducingagent (e.g., dimethylamineborane) containing B.

The plating liquid M1 supplied from the plating liquid supply unit 53(that is, the plating liquid M1 stored in the tank of the plating liquidsupply source 532) is a plating liquid which conducts a preset platingperformance within a preset concentration range. It is determined,whether the plating liquid M1 exhibits the preset plating performance,based on whether a metal film (plating film) having a preset property(e.g., a thickness of 30 nm to 100 nm) is obtained when an electrolessplating is performed by using a preset amount of the plating liquid M1at a preset plating temperature for a predetermined time.

The plating liquid M1 contains a multiple number of components. In orderfor the plating liquid M1 to provide the preset plating performance, aconcentration of each component needs to be within a predeterminedconcentration range. That is, each of the components contained in theplating liquid M1 has a predetermined concentration range which isrequired for the plating liquid M1 to exerts the preset platingperformance. The predetermined concentration range of each component isappropriately determined based on a composition of the plating liquidM1, and the like. Among all the components contained in the platingliquid M1, a concentration of a component which has a predeterminedconcentration range having a smallest difference between an upper limitand a lower limit is defined as a “concentration of the plating liquidM1.” To elaborate, if the component having the smallest differencebetween the upper limit and the lower limit of the predeterminedconcentration range is a metal ion forming the metal film (platingfilm), the concentration of the metal ion is defined as “concentrationof the plating liquid M1” and the predetermined concentration range ofthe metal ion is defined as the “preset concentration range of theplating liquid M1.” If the component having the smallest differencebetween the upper limit and the lower limit of the predeterminedconcentration range is a reducing agent, on the other hand, theconcentration of the reducing agent is defined as “concentration of theplating liquid M1” and the predetermined concentration range of thereducing agent is defined as the “preset concentration range of theplating liquid M1.” Here, the preset concentration range of the platingliquid M1 is expressed as C_(L) (%)˜C_(H) (%).

A concentration and a temperature of the plating liquid M1 supplied fromthe plating liquid supply unit 53 (that is, the plating liquid M1 storedin the tank of the plating liquid supply source 532) is referred to as“initial concentration” and “initial temperature,” and are distinguishedfrom a concentration and a temperature of the plating liquid M1 afterbeing supplied from the plating liquid supply unit 53 to the substrateW1 held by the substrate holding unit 52.

After the plating liquid M1 is supplied from the plating liquid supplyunit 53 onto the substrate W1 held by the substrate holding unit 52, theconcentration and the temperature of the plating liquid M1 are changed.The concentration of the plating liquid M1 is changed as moisture in theplating liquid M1 evaporates and/or as a plating component in theplating liquid M1 is consumed. The temperature of the plating liquid M1is changed as the plating liquid M1 is heated by a plating liquidheating unit 63. To be specific, during a period from when the platingliquid M1 is supplied from the plating liquid supply unit 53 to thesubstrate W1 held by the substrate holding unit 52 to when the suppliedplating liquid M1 reaches the preset plating temperature while beingheated by the plating liquid heating unit 63, the plating component inthe plating liquid M1 is hardly consumed, whereas the moisture in theplating liquid M1 is evaporated. Thus, during this period, theconcentration of the plating liquid M1 is increased. After thetemperature of the plating liquid M1 has reached the preset platingtemperature, since the heating by the plating liquid heating unit 63 iscontinued, the concentration of the plating liquid M1 is stillincreased, though the plating component in the plating liquid M1 isconsumed. That is, since an increase of the concentration of the platingliquid M1 caused by the evaporation of the moisture in the platingliquid M1 is more dominant than a decrease of the concentration of theplating liquid M1 caused by the consumption of the plating component inthe plating liquid M1, the concentration of the plating liquid M1 iskept being increased even after the temperature of the plating liquid M1has reached the preset plating temperature, and reaches the upper limit(i.e., C_(H) (%)) of the preset concentration range, shortly.

The initial temperature of the plating liquid M1 is adjusted to be belowthe preset plating temperature. The plating temperature is a temperaturewhere a plating reaction (a reaction in which the metal ion in theplating liquid M1 is reduced by electrons emitted through an oxidationreaction of the reducing agent in the plating liquid M1 and isprecipitated as a metal) progresses. For example, the platingtemperature may be, but not limited to, 60° C. to 70° C. The initialtemperature of the plating liquid M1 is, by way of non-limiting example,23° C. to 27° C.

The initial concentration of the plating liquid M1 is adjusted such thatthe concentration of the plating liquid M1 at the moment when thetemperature of the plating liquid M1 has reached the preset platingtemperature is equal to or higher than the lower limit (i.e., C_(L) (%))of the preset concentration range and equal to or lower than a medianvalue (i.e., (C_(L)+C_(H))/2) of the preset concentration range.

Assume that the initial concentration of the plating liquid M1 is X (%);the amount of the plating liquid M1 supplied from the plating liquidsupply unit 53 to the substrate W1 held by the substrate holding unit 52is Y (mL) (the plating liquid supply unit 53 does not supplement newplating liquid M1 until the plating with the plating liquid M1 iscompleted after the preset amount of the corresponding plating liquid M1is once supplied); and the amount of the moisture evaporated from thesupplied plating liquid M1 during the period from when the platingliquid M1 is supplied from the plating liquid supply unit 53 to thesubstrate W1 held by the substrate holding unit 52 to when thetemperature of the supplied plating liquid M1 has reached the presetplating temperature while being heated by the plating liquid heatingunit 63 is Z (mL). The concentration (%) of the plating liquid M1 at thetime when the temperature of the plating liquid M1 has reached thepreset plating temperature is expressed as (X×Y)/(Y−Z). Since theconcentration (%) of the plating liquid M1 at the time when it hasreached the preset plating temperature is equal to or higher than C_(L)and equal to or lower than (C_(L)+C_(H))/2, an expression ofC_(L)≦(X×Y)/(Y−Z)≦(C_(L)+C_(H))/2 is established. By modifying thisexpression, the initial concentration X (%) of the plating liquid M1 isexpressed as C_(L)(1−Z/Y)≦×≦(C_(L)+C_(H))(1−Z/Y)/2.

Since Z/Y is less than 1, a lower limit C_(L)(1−Z/Y) of the initialconcentration (%) of the plating liquid M1 is less than C_(L).

When there is established a relationship of Z/Y=1−2C_(L)/(C_(L)+C_(H)),an upper limit (C_(L)+C_(H))(1−Z/Y)/2 of the initial concentration (%)of the plating liquid M1 is equal to C_(L).

When there is established a relationship of Z/Y>1−2C_(L)/(C_(L)+C_(H)),the upper limit (C_(L)+C_(H))(1−Z/Y)/2 of the initial concentration (%)of the plating liquid M1 is less than C_(L).

When there is established a relationship of Z/Y<1−2C_(L)/(C_(L)+C_(H)),the upper limit (C_(L)+C_(H))(1−Z/Y)/2 of the initial concentration (%)of the plating liquid M1 exceeds C_(L).

Accordingly, though the lower limit of the initial concentration (%) ofthe plating liquid M1 is always less than C_(L), the upper limit of theinitial concentration (%) of the plating liquid M1 may be less thanC_(L), equal to C_(L) or exceed C_(L).

As the concentration of the plating liquid M1 at the time when thetemperature of the plating liquid M1 has reached the preset platingtemperature is closer to the lower limit (i.e., C_(L) (%)) of the presetconcentration range, a time period taken until the concentration of theplating liquid M1 reaches the upper limit (i.e., C_(H) (%)) of thepreset concentration range, that is, a time period during which theplating liquid M1 can be used for the plating is lengthened. In thisaspect, the concentration of the plating liquid M1 at the time when thetemperature of the plating liquid M1 has reached the preset platingtemperature is desirably set to be near the lower limit (i.e., C_(L)(%))of the preset concentration range, and, more desirably, set to be thelower limit (i.e., C_(L)(%)) of the preset concentration range.

The concentration of the plating liquid M1 at the time when thetemperature of the plating liquid M1 has reached the preset platingtemperature is larger than the initial concentration thereof. Thus, ifthe initial concentration (%) of the plating liquid M1 is equal to orhigher than C_(L), it may be difficult to adjust the concentration ofthe plating liquid M1 at the time when the temperature of the platingliquid M1 has reached the preset plating temperature to be close to thelower limit (i.e., C_(L) (%)) of the preset concentration range.Therefore, it is desirable that the initial concentration (%) of theplating liquid M1 is less than the lower limit (i.e., C_(L) (%)) of thepreset concentration range.

After supplying the preset amount of the plating liquid M1 a singletime, the plating liquid supply unit 53 does not supply new platingliquid M1 until the plating with the supplied plating liquid M1 iscompleted. Desirably, the preset amount of the plating liquid M1supplied from the plating liquid supply unit 53 at the singe time is 20mL to 200 mL and, more desirably, 30 mL to 100 mL in case that thesubstrate W1 has a diameter of 300 mm. The plating on a single sheet ofsubstrate W1 is performed with the preset amount of the plating liquidM1 which is supplied one time from the plating liquid supply unit 53.That is, the plating on the single sheet of substrate W1 is begun at thetime when the plating liquid M1 supplied to the substrate W1 reaches theplating temperature and is finished at the time when the plating liquidM1 is drained from the substrate W1. Further, the plating liquid M1 isdrained from the substrate W1 before the concentration of the platingliquid M1 reaches the upper limit (i.e., C_(H) (%)) of the presetconcentration range. Since the temperature of the plating liquid M1supplied from the plating liquid supply unit 53 is lower than the presetplating temperature, the plating is not begun or, even if begun,progresses very slowly at the time when the plating liquid M1 issupplied from the plating liquid supply unit 53 to the substrate W1 heldby the substrate holding unit 52. After the plating liquid M1 issupplied from the plating liquid supply unit 53 to the substrate W1which is held by the substrate holding unit 52, the plating is begun atthe time when the temperature of the supplied plating liquid M1 reachesthe preset plating temperature while being heated by the plating liquidheating unit 63. During the plating, the temperature of the platingliquid M1 is maintained at the preset plating temperature by the platingliquid heating unit 63. Accordingly, the plating is performed with theplating liquid M1 which is heated to the preset plating temperature.

A circulation passageway 537 provided with a pump 535 and a heating unit536 is connected to the tank of the plating liquid supply source 532.The plating liquid M1 in the tank is heated to a storage temperaturewhile being circulated through the circulation passageway 537. Here, the“storage temperature” refers to a temperature higher than a roomtemperature and lower than a temperature (plating temperature) where theprecipitation of the metal ion in the plating liquid M1 progressesthrough a self-reaction. In the present exemplary embodiment, though theplating liquid M1 in the tank is heated to the storage temperature, theplating liquid M1 in the tank may be kept at a room temperature.According to the exemplary embodiment, evaporation of the components,deactivation of the reducing agent in the plating liquid M1 or the like,which might occur in case where the plating liquid M1 is heated to theplating temperature within the tank, can be suppressed. Therefore, alifetime of the plating liquid M1 can be lengthened.

A chemical liquid L1 containing various components of the plating liquidM1 is supplied into the tank of the plating liquid supply source 532from a chemical liquid supply source 538 a which stores the chemicalliquid L1 through a supply passageway 538 c which is equipped with aflow rate controller 538 b such as a valve. Further, a diluent liquid L2which dilutes the chemical liquid L1 is supplied into the tank of theplating liquid supply source 532 from a diluent liquid supply source 539a which stores the diluent liquid L2 through a supply passageway 539 cwhich is equipped with a flow rate controller 539 b such as a valve. Thediluent liquid L2 is, for example, pure water. The chemical liquid L1supplied from the chemical liquid supply source 538 a and the diluentliquid L2 supplied from the diluent liquid supply source 539 a aremixed, so that the plating liquid M1 is prepared. At this time, a flowrate of the chemical liquid L1 is adjusted by the flow rate controller538 b and a flow rate of the diluent liquid L2 is adjusted by the flowrate controller 539 b such that the concentration of the plating liquidM1 has the preset concentration.

In the present exemplary embodiment, though only one chemical liquid L1containing all the components of the plating liquid M1 is used, it maybe possible to use two or more chemical liquids each of which contains apart of the components of the plating liquid M1. Further, the componentscontained in each chemical liquid are adjusted such that the two or morechemical liquids contain all the components of the plating liquid M1 asa whole. When using the two or more chemical liquids each containing apart of the components of the plating liquid M1, the two or morechemical liquids are supplied into the tank of the plating liquid supplysource 532 from corresponding two or more chemical liquid supply sourcesstoring the respective chemical liquids through supply passageways eachof which is equipped with flow rate controller such as a valve. As therespective chemical liquids supplied from the two or more chemicalliquid supply sources and the diluent liquid L2 supplied from thediluent liquid supply source 539 a are mixed in the tank, the platingliquid M1 is prepared. At this time, flow rates of the respectivechemical liquids are adjusted by the corresponding flow rate controllersand the flow rate of the diluent liquid L2 is adjusted by the flow ratecontroller 539 b such that the plating liquid M1 is allowed to have thepreset concentration.

A degassing unit (not shown) configured to remove dissolved oxygen anddissolved hydrogen in the plating liquid M1 may be provided in the tankof the plating liquid supply source 532. The degassing unit isconfigured to supply an inert gas such as, but not limited to, anitrogen gas into the tank and dissolve the inert gas such as thenitrogen gas in the plating liquid M1, so that the other gases such asthe oxygen and the hydrogen previously dissolved in the plating liquidM1 may be discharged to the outside of the plating liquid M1. The gasessuch as the oxygen and the hydrogen discharged from the plating liquidM1 may be exhausted from the tank by an exhaust unit (not shown). Thecirculation passageway 537 may be provided with a filter (not shown). Byproviding the filter in the circulation passageway 537, various kinds ofimpurities contained in the plating liquid M1 can be removed. Thecirculation passageway 537 may be further provided with a monitoringunit (not shown) configured to monitor a characteristic of the platingliquid M1. The monitoring unit may be implemented by, for example, atemperature monitoring unit configured to monitor a temperature of theplating liquid M1, a pH monitoring unit configured to monitor a pH ofthe plating liquid M1, or the like.

The plating device 5 is equipped with a nozzle moving mechanism 54configured to move the nozzle 531. The nozzle moving mechanism 54includes an arm 541; a moving body 542 which is configured to be movablealong the arm 541 and has a moving mechanism embedded therein; and arotating/elevating mechanism 543 configured to rotate and move the arm541 up and down. The nozzle 531 is provided at the moving body 542. Thenozzle moving mechanism 54 is capable of moving the nozzle 531 between aposition above a central portion of the substrate W1 held by thesubstrate holding unit 52 and a position above a peripheral portion ofthe substrate W1, and also capable of moving the nozzle 531 up to astand-by position outside a cup 57 to be described later when viewedfrom the top. The controller 3 controls the nozzle moving mechanism 54to adjust a moving timing, a moved position of the nozzle 531, and soforth.

The plating device 5 includes a catalyst solution supply unit 55 a, acleaning liquid supply unit 55 b and a rinse liquid supply unit 55 cconfigured to supply a catalyst solution N1, a cleaning liquid N2 and arinse liquid N3 onto the substrate W1 held by the substrate holding unit52, respectively. Further, it may be appropriately determined dependingon the kind of the plating liquid M1 whether to provide the catalystsolution supply unit 55 a. That is, depending on the kind of the platingliquid M1, the catalyst solution supply unit 55 a may be omitted.

The catalyst solution supply unit 55 a includes a nozzle 551 aconfigured to discharge the catalyst solution N1 onto the substrate W1held by the substrate holding unit 52; and a catalyst solution supplysource 552 a configured to supply the catalyst solution N1 to the nozzle551 a. The catalyst solution N1 is stored in a tank of the catalystsolution supply source 552 a, and the catalyst solution N1 is suppliedto the nozzle 551 a from the catalyst solution supply source 552 athrough a supply passageway 554 a which is provided with a flow ratecontroller such as a valve 553 a. The controller 3 controls the catalystsolution supply unit 55 a to adjust a supply timing of the catalystsolution N1, a supply amount thereof, and so forth.

The cleaning liquid supply unit 55 b includes a nozzle 551 b configuredto discharge the cleaning liquid N2 onto the substrate W1 held by thesubstrate holding unit 52; and a cleaning liquid supply source 552 bconfigured to supply the cleaning liquid N2 to the nozzle 551 b. Thecleaning liquid N2 is stored in a tank of the cleaning liquid supplysource 552 b, and the cleaning liquid N2 is supplied to the nozzle 551 bfrom the cleaning liquid supply source 552 b through a supply passageway554 b which is provided with a flow rate controller such as a valve 553b. The controller 3 controls the cleaning liquid supply unit 55 b toadjust a supply timing of the cleaning liquid N2, a supply amountthereof, and so forth.

The rinse liquid supply unit 55 c includes a nozzle 551 c configured todischarge the rinse liquid N3 onto the substrate W1 held by thesubstrate holding unit 52; and a rinse liquid supply source 552 cconfigured to supply the rinse liquid N3 to the nozzle 551 c. The rinseliquid N3 is stored in a tank of the rinse liquid supply source 552 c,and the rinse liquid N3 is supplied to the nozzle 551 c from the rinseliquid supply source 552 c through a supply passageway 554 c which isprovided with a flow rate controller such as a valve 553 c. Thecontroller 3 controls the rinse liquid supply unit 55 c to adjust asupply timing of the rinse liquid N3, a supply amount thereof, and soforth.

The catalyst solution N1, the cleaning liquid N2 and the rinse liquid N3are pre-treatment liquids for pre-processings that are performed priorto the plating with the plating liquid M1.

The catalyst solution N1 contains a metal ion (e.g., a palladium (Pd)ion, a platinum (Pt) ion, a gold (Au) ion, etc.) having catalyticactivity to an oxidation reaction of the reducing agent in the platingliquid M1. In the electroless plating, in order to start precipitationof the metal ion in the plating liquid M1, an initial film surface (thatis, plating target surface of substrate) needs to have sufficientcatalytic activity to the oxidation reaction of the reducing agent inthe plating liquid M1. Thus, depending on the kind of the plating liquidM1, it may be desirable to process the plating target surface of thesubstrate with the catalyst solution N1 and form a metal film having thecatalytic activity on the plating target surface of the substrate beforestarting the plating with the plating liquid M1. It may be appropriatelydetermined depending on the kind of the plating liquid M1 whether toperform the processing with the catalyst solution N1 before starting theplating. That is, depending on the kind of the plating liquid M1, theprocessing with the catalyst solution N1 may be omitted. The metal filmhaving the catalytic activity is formed through a replacement reaction.In the replacement reaction, a metal forming the plating target surfaceof the substrate (e.g., copper in a copper wiring formed on the platingtarget surface of the substrate) serves as the reducing agent, and themetal ion (e.g., Pd ion) in the catalyst solution N1 is reduced to beprecipitated on the plating target surface of the substrate.

As an example of the cleaning liquid N2, an organic acid such as a malicacid, a succinic acid, a citric acid or a malonic acid, or hydrofluoricacid (DHF) (aqueous solution of hydrogen fluoride) diluted to the extentthat it does not corrode the plating target surface of the substrate maybe used.

As an example of the rinse liquid N3, pure water may be used.

The plating device 5 includes a nozzle moving mechanism 56 configured tomove the nozzles 551 a to 551 c. The nozzle moving mechanism 56 isequipped with an arm 561; a moving body 562 which is configured to bemovable along the arm 561 and has a moving mechanism embedded therein;and a rotating/elevating mechanism 563 configured to rotate and move thearm 561 up and down. The nozzles 551 a to 551 c are provided at themoving body 562. The nozzle moving mechanism 56 is capable of moving thenozzles 551 a to 551 c between a position above the central portion ofthe substrate W1 held by the substrate holding unit 52 and a positionabove the peripheral portion of the substrate W1, and also capable ofmoving the nozzles 551 a to 551 c up to a stand-by position outside thecup 57 to be described later when viewed from the top. In the presentexemplary embodiment, though the nozzles 551 a to 551 c are held by thecommon arm, they may be configured to be held by different arms andmoved independently. The controller 3 controls the nozzle movingmechanism 56 to adjust moving timings, moved positions of the nozzles551 a to 551 c, and so forth by controlling.

The plating device 5 is equipped with the cup 57 having drain openings571 a, 571 b and 571 c. The cup 57 is disposed around the substrateholding unit 52, and is configured to collect various kinds ofprocessing liquids (e.g., plating liquid, catalyst solution, cleaningliquid, rinse liquid, etc.) which are scattered from the substrate W1.The cup 57 is provided with an elevating mechanism 58 configured to movethe cup 57 up and down; and liquid draining mechanisms 59 a, 59 b and 59c configured to collect and drain the various kinds of processingliquids scattered from the substrate W1 through the drain openings 571a, 571 b and 571 c, respectively. By way of example, the plating liquidM1 scattered from the substrate W1 is drained from the liquid drainingmechanism 59 a; the catalyst solution N1 scattered from the substrate W1is drained from the liquid draining mechanism 59 b; and the cleaningliquid N2 and the rinse liquid N3 scattered from the substrate W1 aredrained from the liquid draining mechanism 59 c. The controller 3controls the elevating mechanism 58 to adjust a moving timing, a movedposition of the cup 57, and so forth.

The plating device 5 is also equipped with a top plate 61 disposed abovethe substrate W1 held by the substrate holding unit 52; and an elevatingmechanism 62 configured to move the top plate 61 in a vertical directionand in a horizontal direction. The top plate 61 is disposed above thesubstrate W1 while being spaced apart from the substrate W1. When viewedfrom the top, the top plate 61 has a shape (e.g., a circular shape)corresponding to the shape of the substrate W1, and the size of the topplate 61 is adjusted to cover the substantially entire surface region ofthe substrate W1. The shape and the size of the top plate 61 are notparticularly limited and can be appropriately modified as long as aspace can be formed between the substrate W1 and the top plate 61. Byway of example, when viewed from the top, the top plate 61 may have arectangular shape or the like. Further, the top plate 61 is not providedwith any through hole or opening which can serve a flow path of vaporwhich is generated from the plating liquid M1. The controller 3 controlsthe elevating mechanism 62 to adjust a moving timing, a moved positionof the top plate 61, and so forth by controlling.

The top plate 61 is configured to be moved up and down by the elevatingmechanism 62 independently from the cup 57. Accordingly, carrying-in andcarrying-out of the substrate onto/from the substrate holding unit 52can be facilitated.

The elevating mechanism 62 is configured to move the top plate 61horizontally between a position where the top plate 61 covers thesubstantially entire surface region of the substrate W1 and a positionwhere the top plate 61 does not cover the substantially entire surfaceregion of the substrate W1. Further, the elevating mechanism 62 iscapable of adjusting a distance between the substrate W1 and the topplate 61 (i.e., a volume of a space S formed between the substrate W1and the top plate 61) by moving the top plate 61 in the verticaldirection after moving the top plate 61 to the position where it coversthe substantially entire surface region of the substrate W1. After thetop plate 61 is horizontally moved to the position where it does notcover the substantially entire surface region of the substrate W1, theliquids are supplied from the various nozzles to the substrate W1 heldby the substrate holing unit 52. Further, after the top plate 61 ismoved to the position where it covers the substantially entire surfaceregion of the substrate W1 and the distance between the substrate W1 andthe top plate 61 (i.e., the volume of the space S formed between thesubstrate W1 and the top plate 61) is adjusted, the plating liquid M1supplied to the substrate W1 is heated.

By adjusting the distance between the substrate W1 and the top plate 61after moving the top plate 61 to the position where the top plate 61covers the substantially entire surface region of the substrate W1, thespace S is formed between the substrate W1 held by the substrate holdingunit 52 and the top plate 61 disposed above the substrate W1. The spaceS is surrounded by the cup 57, but is not sealed by the cup 57 and thespace S communicates with an external space (a space within the chamber51). If the moisture in the plating liquid M1 supplied to the substrateW1 held by the substrate holding unit 52 is evaporated, the vaporgenerated from the plating liquid M1 is flown out into the externalspace after staying in the space S. Accordingly, the moisture in theplating liquid M1 supplied to the substrate W1 held by the substrateholding unit 52 is continuously evaporated. By adjusting the volume ofthe space S (e.g., the distance between the substrate W1 held by thesubstrate holding unit 52 and the top plate 61), an evaporation amountof the moisture from the plating liquid M1 can be adjusted. For example,by reducing the volume of the space S, the evaporation amount of themoisture from the plating liquid M1 can be reduced. Accordingly, a sharpincrease of the concentration of the plating liquid M1 caused by theevaporation of the moisture can be suppressed. The moisture that staysin the space S serves as a heat medium when heating, by the platingliquid heating unit 63, the plating liquid M1 supplied onto thesubstrate W1 which is held by the substrate holding unit 52. Thedistance between the substrate W1 held by the substrate holding unit 52and the top plate 61 is appropriately adjusted based on a settemperature of the top plate, a temperature of the plating liquid afterbeing heated, a temperature rising rate of the plating liquid, an amountof the plating liquid on the substrate, and so forth.

The top plate 61 is equipped with the plating liquid heating unit 63configured to heat the plating liquid M1 supplied onto the substrate W1which is held by the substrate holding unit 52. Further, the substrateW1 held by the substrate holding unit 52 is also heated by the platingliquid heating unit 63. The plating liquid heating unit 63 includes aheater such as a lamp heater (e.g., a LED lamp heater) and a heatingwire. In the present exemplary embodiment, the heater of the platingliquid heating unit 63 is embedded within the top plate 61. In thepresent exemplary embodiment, the plating liquid heating unit 63 heatsthe plating liquid M1 on the substrate W1 from above the substrate W1held by the substrate holding unit 52. However, the plating liquidheating unit 63 may be configured to heat the plating liquid M1 on thesubstrate W1 from below the substrate W1 held by the substrate holdingunit 52. In this case, the plating liquid M1 on the substrate W1 isheated by heating the substrate W1 held by the substrate holding unit52. By way of example, the plating liquid heating unit 63 may beprovided at the turntable 522 of the substrate holding unit 52. Thecontroller 3 controls the plating liquid heating unit 63 to adjust aheating timing, a heating temperature, a heating time, and so forth.

<Plating Method>

Now, a plating method performed by the plating apparatus 1 will bediscussed. The plating method performed by plating apparatus 1 includesa plating process of performing a plating on the substrate W1. Theplating in the plating process is performed by the plating devices 5. Anoperation of the plating device 5 is controlled by the controller 3. Theplating method performed by the plating apparatus 1 may further includeother processes than the plating process.

First, a substrate carry-in process is performed. In the substratecarry-in process, the substrate W1 is carried into the plating device 5.The controller 3 controls the transfer device 213 to take out asubstrate W0 from a carrier C placed in the placing section 211 and toplace the taken substrate W0 in the delivery unit 214. Then, thecontroller 3 controls the transfer device 222 to take out the substrateW0 placed in the delivery unit 214 and to carry the taken substrate W0into the plating device 5.

After the substrate carry-in process, a substrate holding process isperformed. In the substrate holding process, the substrate W1 carriedinto the plating device 5 is held by the substrate holding unit 52. Thecontroller 3 controls the elevating mechanism 58 to move the cup 57 downto a preset position, and also controls the elevating mechanism 62 tomove the top plate 61 horizontally to the position where it does notcover the substantially entire surface region of the substrate W1.Accordingly, the transfer device 222 is allowed to access the substrateholding unit 52. The controller 3 controls the transfer device 222 toplace the substrate W1 on the substrate holding unit 52. The substrateW1 is horizontally placed on the turntable 522 while its peripheryportion is held by the chuck 523.

After the substrate holding process, the plating process is performed.The plating in the plating process is performed on the substrate W1 heldby the substrate holding unit 52. The plating device 5 may perform apretreatment process of pre-processing the substrate W1 before theplating process. The pretreatment process may include a cleaningprocess; and a first rinse process which is performed after the cleaningprocess. Further, the pretreatment process may also include a catalystsolution supplying process which is performed after the first rinseprocess. Furthermore, the pretreatment process may further include asecond rinse process which is performed after the catalyst solutionsupplying process.

In the cleaning process, the substrate W1 held by the substrate holdingunit 52 is cleaned. While rotating the substrate W1 held by thesubstrate holding unit 52 at a preset speed by controlling the drivingunit 524, the controller 3 controls the cleaning liquid supply unit 55 bto locate the nozzle 551 b at a position above the substrate W1, and acleaning liquid N2 is supplied onto the substrate W1 from the nozzle 551b. The cleaning liquid N2 supplied onto the substrate W1 is diffused ona surface of the substrate W1 by a centrifugal force which is generatedas the substrate W1 is rotated. As a result, a deposit or the likeadhering to the substrate W1 is removed from the substrate W1. Thecleaning liquid N2 scattered from the substrate W1 is drained throughthe drain opening 571 c of the cup 57 and the liquid draining mechanism59 c. When starting this cleaning process, the controller 3 controls theelevating mechanism 58 to adjust the position of the cup 57 such thatthe drain opening 571 c of the cup 57 is located at a position where itfaces a peripheral edge portion of the substrate W1.

In the first rinse process, the substrate W1 after being cleaned isrinsed. While rotating the substrate W1 held by the substrate holdingunit 52 at a preset speed by controlling the driving unit 524, thecontroller 3 controls the rinse liquid supply unit 55 c to locate thenozzle 551 c at a position above the substrate W1, and a rinse liquid N3is supplied onto the substrate W1 from the nozzle 551 c. The rinseliquid N3 supplied onto the substrate W1 is diffused on the surface ofthe substrate W1 by a centrifugal force which is generated as thesubstrate W1 is rotated. As a result, the cleaning liquid N2 remainingon the substrate W1 is washed away. The rinse liquid N3 scattered fromthe substrate W1 is drained through the drain opening 571 c of the cup57 and the liquid draining mechanism 59 c. When starting this firstrinse process, the controller 3 controls the elevating mechanism 58 toadjust the position of the cup 57 such that the drain opening 571 c ofthe cup 57 is located at a position where it faces the peripheral edgeportion of the substrate W1.

In the catalyst solution supplying process, a metal film (catalystlayer) having catalytic activity is formed on the substrate W1 afterbeing rinsed. While rotating the substrate W1 held by the substrateholding unit 52 at a preset speed by controlling the driving unit 524,the controller 3 controls the catalyst solution supply unit 55 a tolocate the nozzle 551 a at a position above the substrate W1, and acatalyst solution N1 is supplied onto the substrate W1 from the nozzle551 a. The catalyst solution N1 supplied onto the substrate W1 isdiffused on the surface of the substrate W1 by a centrifugal force whichis generated as the substrate W1 is rotated. As a result, a metal film(e.g., a Pd film) having catalytic activity is formed on a platingtarget surface (e.g., a copper wiring formed on the surface of thesubstrate W1). The catalyst solution N1 scattered from the substrate W1is drained through the drain opening 571 b of the cup 57 and the liquiddraining mechanism 59 b. When starting this catalyst solution supplyingprocess, the controller 3 controls the elevating mechanism 58 to adjustthe position of the cup 57 such that the drain opening 571 b of the cup57 is located at a position where it faces the peripheral edge portionof the substrate W1.

In the second rinse process, the substrate W1 on which the catalystlayer is formed is rinsed. While rotating the substrate W1 held by thesubstrate holding unit 52 at a preset speed by controlling the drivingunit 524, the controller 3 controls the rinse liquid supply unit 55 c tolocate the nozzle 551 c at a position above the substrate W1, and therinse liquid N3 is supplied onto the substrate W1 from the nozzle 551 c.The rinse liquid N3 supplied onto the substrate W1 is diffused on thesurface of the substrate W1 by a centrifugal force which is generated asthe substrate W1 is rotated. As a result, the catalyst solution N1remaining on the substrate W1 is washed away. The rinse liquid N3scattered from the substrate W1 is drained through the drain opening 571c of the cup 57 and the liquid draining mechanism 59 c. When startingthis second rinse process, the controller 3 controls the elevatingmechanism 58 to adjust the position of the cup 57 such that the drainopening 571 c of the cup 57 is located at the position where it facesthe peripheral edge portion of the substrate W1

After the above-described pretreatment process is performed, ifnecessary, the plating process is performed. In the plating process,while rotating the substrate W1 held by the substrate holding unit 52 ata low speed (a speed at which the plating liquid M1 supplied onto thesubstrate W1 is not scattered from the substrate W1) by controlling thedriving unit 524 or while maintaining the substrate W1 held by thesubstrate holding unit 52 not to be rotated, the controller 3 controlsthe plating liquid supply unit 53 to locate the nozzle 531 at a positionabove the substrate W1, and the plating liquid M1 is supplied onto thesubstrate W1 from the nozzle 531. After a preset amount of the platingliquid M1 is once supplied onto the substrate W1 from the nozzle 531,the controller 3 controls the plating liquid supply unit 53 not tosupply new plating liquid M1 until the plating with the supplied platingliquid M1 is finished.

The temperature of the plating liquid M1 supplied from the platingliquid supply unit 53 is lower than the preset plating temperature.Thus, at a time point when the plating liquid M1 is supplied onto thesubstrate W1 held by the substrate holding unit 52 from the platingliquid supply unit 53, the plating liquid M1 does not exert the presetplating performance, and the plating reaction is not begun, or, even ifbegun, it progresses very slowly.

After the plating liquid M1 is supplied onto the substrate W1 held bythe substrate holding unit 52, the controller 3 controls the elevatingmechanism 62 to move the top plate 61 horizontally up to the positionwhere the top plate 61 covers the substantially entire surface region ofthe substrate W1 and, then, to move the top plate 61 down, so that thetop plate 61 is located close to the substrate W1. Accordingly, when theplating liquid M1 supplied onto the substrate W1 is heated by theplating liquid heating unit 63, there is formed the space S between thesubstrate W1 held by the substrate holding unit 52 and the top plate 61.The space S is surrounded by the cup 57. The space S is not sealed bythe cup 57 and communicates with the external space. After the top plate61 is placed close to the substrate W1, the controller 3 controls theplating liquid heating unit 63 to heat the plating liquid M1 on thesubstrate W1 to the preset plating temperature. The controller 3 maycontrol the plating liquid heating unit 63 to heat the substrate W1before the plating liquid M1 is supplied. In such a case, the controller3 controls the elevating mechanism 62 to move the top plate 61horizontally up to the position where it covers the substantially entiresurface region of the substrate W1 and, then, to move the top plate 61down, so that the top plate 61 is located near the substrate W1. Then,by controlling the plating liquid heating unit 63, preliminary heatingon the substrate W1 is performed.

After the plating liquid M1 is supplied from the plating liquid supplyunit 53 onto the substrate W1 held by the substrate holing unit 52, at atime point when the temperature of the plating liquid M1 has reached thepreset plating temperature while being heated by the plating liquidheating unit 63, the plating liquid M1 exerts the preset platingperformance, so that the plating is begun. During the plating, thecontroller 3 controls the plating liquid heating unit 63 to allow thetemperature of the plating liquid M1 to be maintained at the presetplating temperature. Accordingly, a plating film is formed on theplating target surface of the substrate W1 (on the metal film (e.g., thePd film), which has catalytic activity and is formed on the surface ofthe substrate W1, in case that the catalyst solution supplying processis performed).

Through the above processes, the plating on the single sheet ofsubstrate W1 is performed with the plating liquid M1 heated to thepreset plating temperature. That is, the controller 3 controls theplating liquid supply unit 53 and the plating liquid heating unit 63such that, after the preset amount of the plating liquid M1 is suppliedto the substrate W1 held by the substrate holding unit 52 one time, thesupplied plating liquid M1 is heated to the preset plating temperatureby the plating liquid heating unit 63, and the plating is performed withthe plating liquid M1 heated to the preset plating temperature.

After the plating liquid M1 is supplied from the plating liquid supplyunit 53 onto the substrate W1 held by the substrate holding unit 52, thesupplied plating liquid M1 is heated by the plating liquid heating unit63. As a result, the moisture in the plating liquid M1 is evaporated,and the vapor generated from the plating liquid M1 stays in the space S.The space S is surrounded by the cup 57, but is not sealed by the cup 57and communicates with the external space (space within the chamber 51).The vapor generated from the plating liquid M1 is flown into theexternal space after staying in the space S. Accordingly, the moisturein the plating liquid M1 is continuously evaporated. The evaporationamount of the moisture from the plating liquid M1 can be adjusted bycontrolling the volume of the space S (for example, the distance betweenthe top plate 61 and the substrate W1 held by the substrate holding unit52). For instance, by reducing the volume of the space S, theevaporation amount of the moisture from the plating liquid M1 can bereduced, and, thus, the sharp increase of the concentration of theplating liquid M1 caused by the evaporation of the moisture can besuppressed. The distance between the top plate 61 and the substrate W1held by the substrate holding unit 52 may be appropriately controlledbased on the set temperature of the top plate, the temperature of theplating liquid after being heated, the temperature rising rate of theplating liquid, the amount of the plating liquid on the substrate, andso forth.

As the plating liquid M1 is heated by the plating liquid heating unit 63after being supplied from the plating liquid supply unit 53 onto thesubstrate W1 held by the substrate holding unit 52, the temperature ofthe plating liquid M1 is increased, and the moisture in the platingliquid M1 is evaporated, so that the concentration of the plating liquidM1 is increased. As a result, the concentration of the plating liquid M1at a time when the temperature of the plating liquid M1 has reached thepreset plating temperature becomes equal to or higher than the lowerlimit (i.e., C_(L)(%)) of the preset concentration range or equal to orlower than the median value (i.e., (C_(L)+C_(H))/2) of the presetconcentration range.

The plating component of the plating liquid M1 is consumed after thetemperature of the plating liquid M1 reaches the preset platingtemperature. Since, however, the heating by the plating liquid heatingunit 63 is continued, the concentration of the plating liquid M1 isincreased. That is, since the increase of the concentration of theplating liquid M1 caused by the evaporation of the moisture from theplating liquid M1 is more dominant than the decrease of theconcentration of the plating liquid M1 caused by the consumption of theplating component within the plating liquid M1, the concentration of theplating liquid M1 is increased even after the plating liquid M1 reachesthe preset plating temperature, and reaches the upper limit (i.e., C_(H)(%)) of the preset concentration range, shortly.

As the concentration of the plating liquid M1 at the time when thetemperature of the plating liquid M1 has reached the preset platingtemperature is closer to the lower limit (i.e., C_(L) (%)) of the presetconcentration range, a time period taken until the concentration of theplating liquid M1 reaches the upper limit (i.e., C_(H) (%)) of thepreset concentration range, that is, a time period during which theplating liquid M1 is used for the plating is lengthened.

The controller 3 finishes the plating by draining the plating liquid M1from the substrate W1 before the concentration of the plating liquid M1reaches the upper limit (i.e., C_(H) (%)) of the preset concentrationrange. When finishing the plating, the controller 3 controls theelevating mechanism 62 to move the top plate 61 up to a preset positionand to move the top plate 61 horizontally up to the position where thetop plate 61 does not cover the substantially entire surface region ofthe substrate W1. Thereafter, while rotating the substrate W1 held bythe substrate holding unit 52 at a preset speed by controlling thedriving unit 524, the controller 3 controls the rinse liquid supply unit55 c to locate the nozzle 551 c at a position above the substrate W1,and the rinse liquid N3 is supplied onto the substrate W1 from thenozzle 551 c. The plating liquid M1 and the rinse liquid N3 on thesubstrate W1 are scattered from the substrate W1 by a centrifugal forcewhich is generated as the substrate W1 is rotated, and the platingliquid M1 and the rinse liquid N3 scattered from the substrate W1 aredrained through the drain opening 571 a of the cup 57 and the liquiddraining mechanism 59 a. When finishing the plating, the controller 3controls the elevating mechanism 58 to adjust the position of the cup 57such that the drain opening 571 a of the cup 57 is located at theposition where it faces the peripheral edge portion of the substrate W1.

In the plating device 5, it is desirable to perform a drying process ofdrying the substrate W1 after the plating process. In the dryingprocess, the substrate W1 can be dried naturally by rotating thesubstrate W1, or by discharging a drying solvent or a drying gas to thesubstrate W1.

After the plating process, a substrate carry-out process is performed.In the substrate carry-out process, the substrate W2 on which theplating is completed is carried out from the plating device 5. At thistime, the controller 3 controls the transfer device 222 to take out thesubstrate W2 from the plating device 5 and place the taken substrate W2in the delivery unit 214. Then, the controller 3 controls the transferdevice 213 to take out the substrate W2 from the delivery unit 214 andaccommodate the substrate W2 in the carrier C in the placing section211.

From the foregoing, it will be appreciated that various embodiments ofthe present disclosure have been described herein for purposes ofillustration, and that various modifications may be made withoutdeparting from the scope and spirit of the present disclosure.Accordingly, the various embodiments disclosed herein are not intendedto be limiting.

We claim:
 1. A plating apparatus having a plating device configured toperform a plating on a substrate at a preset plating temperature; and acontroller configured to control an operation of the plating device,wherein the plating device comprises: a plating liquid supply unitconfigured to supply, to the substrate, a plating liquid which allowedto exert a preset plating performance within a preset concentrationrange; and a plating liquid heating unit configured to heat the platingliquid supplied to the substrate to the preset plating temperature,wherein the plating liquid supplied to the substrate from the platingliquid supply unit has an initial temperature adjusted to be lower thanthe preset plating temperature, and an initial concentration adjustedsuch that a concentration of the plating liquid at a moment when atemperature of the plating liquid has reached the preset platingtemperature while being heated by the plating liquid heating unit isequal to or higher than a lower limit of the preset concentration rangeand equal to or below a median value of the preset concentration range,and the controller controls the plating liquid supply unit and theplating liquid heating unit to perform, by supplying a preset amount ofthe plating liquid to the substrate a single time and heating thesupplied plating liquid to the preset plating temperature, the platingwith the plating liquid heated to the preset plating temperature.
 2. Theplating apparatus of claim 1, wherein the initial concentration isadjusted such that the concentration of the plating liquid at the momentwhen the temperature of the plating liquid has reached the presetplating temperature is close to the lower limit of the presetconcentration range.
 3. The plating apparatus of claim 1, wherein theinitial concentration is adjusted to be lower than the lower limit ofthe preset concentration range.
 4. The plating apparatus of claim 1,wherein the plating device is equipped with a top plate disposed abovethe substrate, and when the plating liquid supplied to the substrate isheated by the plating liquid heating unit, a space in which vaporgenerated from the plating liquid supplied to the substrate stays isformed between the substrate and the top plate.
 5. A plating method ofperforming a plating on a substrate at a preset plating temperature, theplating method comprising: a plating liquid supplying process ofsupplying, to the substrate, a plating liquid which exerts a presetplating performance within a preset concentration range and which has aninitial temperature adjusted to be lower than the preset platingtemperature; and an initial concentration adjusted such that aconcentration of the plating liquid at a moment when a temperature ofthe plating liquid has reached the preset plating temperature is equalto or higher than a lower limit of the preset concentration range andequal to or below a median value of the preset concentration range; anda plating liquid heating process of heating the plating liquid suppliedto the substrate to the preset plating temperature, wherein a presetamount of the plating liquid is supplied to the substrate a single timein the plating liquid supplying process, and in the plating liquidheating process, the plating liquid supplied in the plating liquidsupplying process is heated to the preset plating temperature, and theplating is performed with the plating liquid heated to the presetplating temperature.
 6. The plating method of claim 5, wherein theinitial concentration is adjusted such that the concentration of theplating liquid at the moment when the temperature of the plating liquidhas reached the preset plating temperature is close to the lower limitof the preset concentration range.
 7. The plating method of claim 5,wherein the initial concentration is adjusted to be lower than the lowerlimit of the preset concentration range.
 8. The plating method of claim5, wherein the plating liquid heating process is performed in a statewhere a space in which vapor generated from the plating liquid suppliedto the substrate stays is formed between the substrate and a top platedisposed above the substrate.
 9. A computer-readable recording mediumhaving stored thereon computer-executable instructions that, in responseto execution, cause a plating apparatus to perform a plating method asclaimed in claim 5.